THE ARTIFICIAL PRODUCTION OF DIAMOND. 



83 



residue generally resulted from the small iron globules, and also from the dust, but 

 never anything from the ingot remaining in the crucible. 



In several experiments water was admitted, which played directly on the crucible, 

 the upper carbons resting on the rim prevented its upsetting by the force of the 

 water, and still there was no residue. In one experiment the carbons were lifted and 

 the charge flowed out, forming spherules of varying size in the water. There was a 

 very small diamond residue from these spherules. 



In one experiment a crucible was filled with iron and carbon and closed by a tight 

 carbon cover, a hole bored in the side of the crucible, a massive block of iron placed 



4 carbons //_ 



Crucible // 



Fig. 11. 



close opposite the hole and the crucible boiled, the vacuum being under 1 mm. No 

 crystallised residue was found in the deposit on the iron block from this high 

 velocity jet of vapour of iron and carbon. 



In another experiment a powerful electro-magnet was provided with poles to give 

 a concentrated field, and an arc struck between two carbons, arranged to burn 

 within this field and regulated from without by hand. There was an iron block 

 upon which the arc directed by the field could play and condense its carbon vapour. 

 The analysis gave no diamond. 



VOL. ocxx. A. N 



